1. Field of the Invention
This invention relates to a multi-piece solid golf ball having satisfactory flight performance, spin properties and feel.
2. Prior Art
Golf balls having a variety of constructions are available on the market. Of these, the majority of golf balls now on the market are two-piece solid golf balls having a rubber-based core enclosed within a cover made of ionomer resin or the like, and thread-wound golf balls comprising a solid or liquid center about which is wound a rubber thread which is in turn enclosed within a cover.
Most golfers of ordinary skill use two-piece solid golf balls because of their excellent flight performance and durability. However, the two-piece solid golf balls have a very hard feel when hit, and are difficult to control because of the rapid separation of the ball from the head of the club. For this reason and others, many professional golfers and low-handicap golfers prefer thread-wound golf balls to two-piece solid golf balls. Although thread-wound golf balls have a superior feel and controllability, their flight distance and durability fall short of those for two-piece solid golf balls.
Since two-piece solid golf balls and thread-wound golf balls today provide mutually opposing features, golfers select which type of ball to use based on their level of skill and personal preference.
This situation has prompted efforts to approximate the feel of a thread-wound golf ball in a solid golf ball. As a result, a number of soft, two-piece solid golf balls have been proposed. A soft core is used to obtain such soft two-piece solid golf balls, but making the core softer lowers the resilience of the golf ball, compromises flight performance, and also markedly reduces durability. As a result, not only do these balls lack the excellent flight performance and durability characteristic of ordinary two-piece solid golf balls, but they are often in fact unfit for actual use. More specifically, the structure of prior art two-piece solid golf balls is determined depending on which of the three features of softness, resilience, and durability is more important. Any attempt to improve one of these features compromises the remaining features.
A variety of three-piece solid golf balls having an intermediate layer interposed between the core and the cover were recently proposed. For example, JP-A 142228/1994 and 244174/1992 disclose intermediate layers of polyester resin and polyamide resin, respectively. They cannot fully meet the requirements of flight distance, feel, and spin properties (especially spin properties upon short iron shots) at the same time.
Therefore, there is a desire to have a golf ball which gives a soft pleasant feel when hit and remains durable, which receives relatively less spin when hit with a wood or long iron club, but maintains initial spin during flight so that an increased carry is available with good controllability, and which offers satisfactory spin properties when hit with a short iron club.